Internal-combustion engine



R. s. CARTER 1,743,023

INTERNAL COMBUSTI ON ENGINE Jan. 7, 1930.

Filed July 5. 1926 4 Sheets-Sheet 1 Jan. 7, 1930. 5 CARTER 1,743,023

INTERNAL COMBUSTION ENGINE Filed July 5. 1926 4 Shets-Sheet 2 Jam. 1?,393%,

R. s. CARTER INTERNAL COMBUSTION ENGINE July 5. 1926 4 Sheets-SheetFiled W .H We

Jan. 7, 1930. w R 5 CARTER 1,743,023

INTERNAL COMBUS TI ON ENGINE Filed July 5. 1926 4 Sheets-Sheet 4 87 iiNVENTOR 55 V Patented Jan. 7, 1939 UNITED STATES "PAT r Fries RUSSELLS. CARTER, O1? HEWLETT, NEW YORK INTERNAL-COMBUSTION ENGINE Applicationfiled July 3,1926. Serial No. 120,311.

There is more or less crank case contamination, as is well known, in theoperation of internal combustion engines on liquid fuels of considerablylighter gravity than the lubricating oil. That is to say, more or lessof the fuel finds its way past the piston into the lubricating oil, andthis reduces the viscosity of the lubricant and its lubricatingqualities. It has heretofore been proposed to distill the lubricatingoil, i. e. vaporize the lighter fuel oil, by applying heat to thefuellubricant mixture, and usually this has been done by means of avaporizer, external to the engine, between which and the lubricant sumpa circulation of the fuel-lubricant mixture is maintained while theengine is in operation. While this practice limits the degree ofcontamination, it does not prevent crank case contamination as isobvious.

I contemplate recovering the fuel which enters the crevice between thepiston and cylinder wall before it has an opportunity to mix with themain body of lubricating oil. With the common hollow type of piston, Iprefer to direct this escaping fuel into the hollow of the piston, fromwhence it can be recaptured readily. Also I contemplate using the enginepiston or pistons to vaporize the liquid fuel entering the crevicesbetween the pistons and the cylinder walls. Ordinarily the piston isquite the hottest part of an internal combustion engine and is a sourceof adequate heat to vaporize the escaped fuel. Furthermore, thereby Imake use of the latent heat of vaporization to moderate the temperatureof the piston. The fuel may be vaporized on the outside of or within thepiston and the products of the vaporization can be re turned to thecombustion spaces directly, or removed from the engine case by suction,or blown out, and thence can be discharged into the atmosphere or passedinto the engine intake passages, or returned to the body of liquid fuelat a convenient point, in the last case usually after condensation.Ordinarily I use suction when the vapors are to be removed from theengine case. The quantity of lubricating oil taken out of this casealong with the fuel vapor can be limited by oil traps placed along theoutgoing lines,or when the fuel is vaporized, by arranging to take thefuel vapor from a high point in some chamber or space where the fuelvapor tends to collect above the lubricating oil because of the greaterspecific gravity of the latter; both expedients can be resorted toconjointly. For example, in vertical engines, when the fuel is deliveredinto or developed within the cylinder space below the piston heads inthe form of vapor, openended outlet pipes, telescopic or otherwise, canbe extendedupwardly to points close to the underside of the pistonheads, or at least well up into the cylincers, to withdraw the vapor.Especially in such situations I contemplate sweeping out the fuel vaporby an air flow of large volume, and to assist this sweeping out of thefuel vapor without entraining an undue amount of the lubricant, the airto sweep out the vapor can be admitted into the engine case throughopen-ended inlet pipes similarly extending up into each cylinder andplaced more or less diametrically opposite the outlet pipes, so that theair flow is substantially localized to the region of the densest fuelvapor and above the region of considerable crank case fog, i. e., abovethe region of the denser atomized or vaporized lubricant. vVith certainengine constructions however,

it may be desirable to employ air outlet or inlet ports opening into thecrank case below the cylinders in addition to or as substitute for theoutlet and inlet pipes within the cylinders. -A regulating valve orvalves may be added to proportion the air flow these two ways asconditions dictate.

Locating the inlet pipe, or both the inlet and outlet pipes, with its ortheir ends within the cylinder space accomplishes another i1nportantfunction, namely, the, air flow tends to cool the piston head by reasonof its contact with or through ventilation of the region of the pistonhead. An air inlet pipe, or both inlet and outlet pipes, within eachcylinder space is useful for this purpose alone, that is to say,independently of and unaccompanied by prevention of crank casecontamination.

About an internal combustion engine there are a number of parts subjectto reduced atthrough the crank case.

' case.

mospheric pressure and hence potential sources of suction to create theair flow However, since an air flow of large volume seems preferable,the air intake of the carburetor is the most suitable natural suctionsource from this standpoint, and furthermore this arrangement preservesany recovered fuel by returning it to the engine for combustion use andtends to riclien the combustion mixture for a time after starting whenan unusually richmi'xture is desirable. If taking all the combustion airthrough the engine case tends 'to extract too much of the lubricatingoil or imposes an unnecessary restriction on the floiv of combustionair, a part of thejcombustion air can be furnished independently ofthecrank case, only a part being taken through the A fixed leak fromatmosphere, for example, will permit acertain part of suchsuction-created air flow to 'be taken direct from the atmosphere; or aregulating valve may be interposed in the leak to permit regulationof--the -part of the combustion air tobe taken through the engine caseand the part to be furnished independently of the crank case.

'Such a valve maybe independently adjusted, or interconnected forconjoint operation with one or more of the engine controls. For example,it may be so interconnected with they throttle thatincreasing thethrottle opening causes a'larger part of the total combustion air to betaken in independently of the engine case, thus relieving therestriction on the air flowfwhen high speeds or large loads demand greatpower from the 'engine,-as hereafter referredto again. Also for example,since "the greatest deliveries of fuel in the form of liquid to thecombustion space occur when the engine is choked, the regulating valvemay beinterconnected with the choke, either independently of thethrottle or conjointly with the throttle but in such manner that all ora large part of the total air is taken through the crank case wheneverthe choke valve is closed. regardless of the'position of the throttle.This produces the maximum fuel-reinovingflow at the time when mostneeded;

'however, this arrangement also produces maximum piston cooling atstarting, when quick heating of the engine is frequently highlydesirable, and hence where such cooling predominates another relationmay be hereafter. I

If desirable, the suction ofthe carburetor can be aided or supplanted incausing the air flow through the engine case. A blowermay be usedeitherengine driven or driven 'byits own motor; the engine pistons also may beused forthis'purpose as hereafter explained. Thus if the factorof pistoncooling suflers unduly by limiting-theair flow to less'thanmaximumathigh loads and high s'peedsithat is to say, at those times whenheatisdeveloped "at the greatest rate, such aids or substitutes "plugsat 5,

so as to obtain the maximum or an increased flow through the engine caseat wide open throttle without unduly limiting the volume of combustionair supplied to the engine. 7

Such aids may be kept in constant operation so long as the engine isrunning, or brought into operation'oiily as the throttle. position orother conditions dictate.

Regulation can also be obtained by regulating the tendency of the aid tomove air, or by a passage-restricting valve or valves, or by valvedleaks to or from the atmosphere on the carburetor side of the valve, orthe side toward the aid, or both. By'employing a suitable device orarrangement, a greater volume of air may be employed for cooling, forexample, than is required for combustion, the part not needed forcombustion being bled off. A blower' detailsof construction which bringabout the recovery of the fuel. a V

The invention is illustrated in the accompanying drawings,ratherdiagrammatically, in connection with multi-cylinder engines. Fig.1 is a vertical section of such an internal combustion engine with myinvention applied. Fig. 2 is an elevation of the same' engine, partly insection. Fig. 3 is a sec tional plan View of the same substantiallyalong the broken line III-III of Fig. 1. Fig. 4 is a perspectivediagrammatically illustrating the interconnection of the throttle, chokeand by-pass regulating valves of Figs. 1 and 2. Figs. 5, 6 and 7 arerespectively a vertical section, elevation and plan of one of the inletvalve structures of the engine of Fig. 1. Fig. 8 illustrates anotherporting for the admission of air to the cylinder spaces. Fig. 9 is avertical section of an engine embodying another form of my invention.Fig. 10 is an elevation of the engine of Fig. 9. Fig. 11 is a sectionalplan thereof, substantially on the line XI-XI of Fig. 9. Fig. 12 is asectional elevation of a modification of a detail. Figs. 13, 14, '15 and16 are'sectional views of further modifications.

Many details of engine construction have been omitted from variousfigures of. the

drawing, as will be apparent. Referring first to Figs. 1 to 7: Theengine case comprising the usual crank case 1, the cylinder'block orblocks'2, which are'vertically mounted'therei on, and the head '3, whichis illustrated as detachable from the-cylinder block. Custoimaryenginevalves areindicated at 4, spark carburetor at 6, throttle valve at'7,-int'akemanifold at 8, andth'e pistons at i 9 within the cylinders.The pistons are of hollow type, as will be seen from Fig. 1, andsomewhat below the piston head and piston rings 14 are pierced with aseries of holes 10, which, externally of the piston, open intocircumferential grooves 11, one in each piston. Liquid fuel passing thepiston heads and moving toward the lubricant sump in the bottom of thecrank case 1, enters the grooves 11 and therefrom is directed throughthe ports 10 to the inside surface of the wall of the respective piston.If desired, an oil collecting ring 12 may be located in the groove 11 toassist in trapping the fuel and direct ing it into the ports 10; by oilcollecting ring, it will be understood of course, I refer to pie tonrings which are pierced radially and usually grooved circumfercntially,such as are commonly used in internal combustion engines to prevent anexcess of lubricating oil from creeping upwardly along the cylinder wallinto the combustion chamber, If desired also, additional rows or seriesof ports can be pierced lower down in the piston walls to intercept anyfuel passing the first series; another such row is illustrated at 13together with its own collecting ring 12, but usually one or two rows ofports 10 in the upper half of the piston will be sufficient. The fuelpassing through the ports 10 and 13 in liquid form, along with anylubricating oil that may be entrained, is delivered into the receptaclesor lips 17 and 18 respectively placed below each series of holes, whichcause the fluid to be retained in contact with the piston walls longenough to permit the fuel to be vaporized; the unvaporized oil will findits way down the piston walls into the sump. The upper edge of each lipmay be placed below lLS ports as illustrated, so that even if the lipshould become t ll d with fuel and oil, there will be no tendency forthis accumulation to cause a backward flowthrough the ports 10. Further,the upper edges of the lips (see lip 17, Fig. 1) may be turned back awayfrom the axis of the piston so that any liquid thrown out of thereceiver by the reciprocation of the piston will be thrown against thewalls of the piston rather than toward the axis from whence the liquidmight fall into the lubricant sump. It will be understood however thatthe lips or receivers for the fuel ano oil may assume various forms,their purpose being, in Figs. 1 to 7, principally to delay the immediateflow of the fuel liquid down the piston walls and thence into thelubricant sump and to cause the fuel liquid to be retained on the wallsof or in heat-exchange relation to the piston for sufficient time topermit the heat of the piston to vaporize the fuel; in certain cases, noadded lips may be needed at all, the mere length of the piston orirregularities of its surface retaining the fuel long enough to assurevaporization.

The fuel vapor thus produced in the hollow of each piston is removedthrough the outlet stand pipes 21, of which thereis one or more for eachcylinder as appears from Fig. 3. These stand pipes reach up into thecylinders from below and are secured by the brackets 22, their upperopen ends being telescoped by the pistons as the latter move downwardly,and reaching not quite to the piston heads when the pistons are at theextreme ends of their expansion strokes. Air is admitted to the cylinderspaces and the hollows of the pistons through similar stand pipes 23;cthat is to say the stand pipes 23, open at their upper ends, alsoextend upwardly into the. cylinder chambers from below and are carriedby brackets 22 and reach not quite to the piston heads when the pistonsare at the ends of their expansion strokes. The stand pipes 21 and 23 ofeach cylinder are located more or less opposite each other as appearsfrom Fig. 3. For convenience or construction, I usually use a singleinlet structure 24 for each two adjacent stand pipes 23 (see Figs. 1, 3and 5), and these structures can be ex-- tended up into the chambercontaining the valve push rods 25 as illustrated in Fig. 1, so that theair flow aids in cooling the push rods and valve springs as well as toextract the fuel vapor and cool the pistons. Louvers 26 and 27 in theplates closing the chamber for the push rods permit the entry of air andwith cloth or wire screens 28 clean the incoming air. Usually I alsoarrange the outlet pipes 21 in pairs similar to the pairing of the pipes23 (see Fig. 3), and all these outlet pipes open into an outlet manifold31 running substantially the length of the engine. The manifold 31, inturn, opens by means of a passage 32 extending across air intake of thecarburetor 6, so that the latter may take all its air by way of thepassages 32 and 33 and through the engine casing.

over the outlet pipes 21tends to produce a noticeable inspiration andaspiration through the pipes 21 and interchange of air through tiiemanifold 31, with a surging tending to disturb the desired delivery ofair to the car-, buretor and the proportions of the combustion mixture,valves such as 33 can be added to prevent air passing backwards from themanifold into the pipes 21. These valves 33 can be light flap valves,one for each of the;

pipes 21, closed by gravity and any tendency there may be for the air toflow backwards. Stops 3 1 prevent these flap valves opening too far, andfor convenience they are mounted in cages 35, one cage and pair ofvalves, these cages being inserted into the manifold 31 at the feet ofthe pipes 21 and the openings for the cages covered by plates 36.

The entire volume of the combustion air,i3

the engine to the- If the reciprocating action of the pistons;

for each pair of pipes 21;;

more or less to the exclusion of air "taken throughthe engine case byWay of the crosspassage 32; thisleak is shown in the drawings as closedby a'flap valve 41 carried on a pintel '42. In the present instance,this added valve '41 g is 'interconnected with the carburetor throttle 7and choke in such a manner that more or less of'the combustion'iair istaken 32o in throughthis leak'39 as'the engine i'scalled on for morepower -'for higher speeds or greater-loads, thereby more or less removng therestrictionimposed by theengine case=on the flow of combustion airandpermitting 125 greater charges of combustible mixture to be fed-tothe cylinders, and also when startingthe engine, at :which latter'timeit is ifre quently desirable-that the cooling effect of theair flowon'the'pistons be eliminated in 30 order that the engine'maywarm up asquickly as possible. This interconnection of the valve is bestillustrated in the diagram of j 4. As appears in that figure, thethrottle valve 7 is operated bythe rod'43 andvan arm 85 44 on thethrottle'valve shaftyactingagainst a spring 38 which tends to close thethrottle. An oppositely extending =arm45 on the throttle shaft connectswith a rod 46 which leads to an arm 47 on, the 'pintle42 no of theleakvalve 41, and-a collar 48 is fixed to this-rod 46 in such a positionas to strike the arm 47 and open the valve41 atth'e proper time, usuallyafter the throttle 7 has been opened to a certain extent, say aboutonells-eighth or one-quarter'of its ull opening; thereafter collar 48opensthe-leakvalve along with the throttle according to some properratio as will be understood A spring 49 works against the thrust of thecollar 48 60 and closes'the valve 41 when released by the collar. Forconnection'to the choke, an oppositely extending arm 50 on'the pintle 42is arranged to receive an extension of the choke operating rod 51, whichis shown provided with a collar-52 whereby the rod51 can close the choke40 against a-spring tendingtoopen it, and also witha collar53"for'picking up the arm and thereby-opening the valve 41; the v collar'53 is usually so placed-on the'rod 51 Mthat'the choke rod 51 doesnot'open the leaik valve 41 unlessthe choke 40 is itself moved to nearlyclosed position, or to {that position usually given'to the choke instarting the engine in cold weather. A slidin collar '56 on the rod 46,fixed collar 57"a'nd interposed cold piston to rise more 'quickly to apoint where the engine acts well and Where the ducetl spri'ng 58 may actto or assist inclosin'gthe leak'valve'41, thesp'rin'g 58 and sliding ofand-the -positionof therod 46.

Ordinarily I prefer this method ofopera- .tion, namely, eliminating ormaterially reducing-the 'flow of air through the engine 7 case,-whilethechoke isclosed, since this oper- 'ation delays "thebe'gin'ning ofpiston cooling for a time and"permits the temperature of a piston'mayact asa vaporizer. While the largest quantities of fuelindiquid formenter the combustion spaces at this time, when the engine'iscold andchoked,=the increase in contamination is not-so great as mightbeexpectedsince the 'fuel liquid does not pass 35 over thepistons-and enter thesump immediately, but is delayed by the piston'rings and passes therings rather slowly. Furthermore, I contemplate making the lip or lips17 and 18 of such capacity, as reservoirs, as

to retain such liquid aspas'sesthe rings until the piston heats upand'the-air flow is restored. Inthe'usual operation ofthe choketherefore I contemplate that the air flow will be restored in'time toperform its function of -'95 extracting the escaping 'fuel.

Figs. -1-'to"7 also illustrateone 'manner of aiding the 'engine suctionin causing the air flow-through the engine case, such aid beingaiforded'by the pistons themselves in conjunction with the valves 33 onthe outlet pipes and further valves 59 on the air inlet pipes. Oneof-these valves 59'is provided for each inlet pipe 23 and they are soarranged as to permit a floW-of'air into the cylinder spaces but toprevent'a flow outwardly from the cylinder spaces through'the pipes 23.As shown in Fi s. 5, 6,'and 7 th'ese'valvesmay'be intro readily bydividing the air inlet 24 Q which of a partition 60, and hanging'on thispartition the two corresponding flap valves 59; these may be assisted totheir closed positions by light springs, such as61, although it will beapparent that the tendency for the ai-r'to' 115 f flow backwards out ofthe cylinders,--through the pipes 23, as the pistons reciprocate willdagain forcing out this air through the "pipe 21, and thus "the pistons,

:of them selves, producing an air 'flow through the cylinder chambers.If'necessary, "the restriction to a free interchange of air "from 130serves two of the pipes 23, as by means I cylinder to cylinder throughthe crank case may be increased tothe desired extent, as by means ofplates 62 of thin metal extending across the lower ends of thecylinders, but pierced, of course, for the passage of the pipes 21 and23 and the connecting rods extending etween the pistons and the crankshaft. Other means for increasing the restriction or even substantiallyentirely preventing the interchange can be devised readily. I have alsoillustrated an oil trap, in this case supplemental to the pipes 21 and23, for reducing the amount of oil taken out of the engine case alongwith the fuel. Here the trap consists simply of a small sump 63 intowhich the manifold 31 drains; a U-shaped pipe leading from this sump andopening within the crank case permits accumulations of oil in the sump63 to pass therefrom into the crank case with.- out permitting air topass from the crank case into the sump 63 and thence into the manifold31 under the suction of the carburetor. I have also illustrated a heaterfor the manifold 31 and the air going to the carburetor, this heaterbeing in the form of a passage 65 running beside the manifold 31 intowhich more or less of the engine exhaust can be directed at 66 and ledout at 67 (Figs. 1 and 2) as will be understood.

While, as before pointed out, an inlet pipe leading well up into eachcylinder, such as 23 for example, is preferable in most instances, itmay be desirable or sufficient in some instances to admit air directlyinto the crank case by one or a distributed lot of holes 5 L (Fig. 1),either supplemental to or as a substitute for the pipes deliveringdirectly into the cylinder chambers; when supplemental to such inletpipes, the flow the two ways may be regulated, and for. the presentpurposes the holes 54: may be regarded as so chosen as to size and insuch numbers as to afford suitable fixed regulation. In other cases thepipes 23 may be dispensed with by piercing an inlet port or ports in thewall of each cylinder at a point uncovered by the piston on its upwardstroke. Such a construction is shown in Fig. 8, an inlet port for thesweeping out air being shown at 68. Reference characters heretofore usedappearing on this figure identify various parts, so that theconstruction will be understood.

Figs. 9, 10 and 11 illustrate principally the use of a blower 7 5 inconnection with or as part of my invention. Various modifications ofgeneral application are also illustrated. Of the latter character, itwill be observed that the lip which aids in retaining the liquid fuel onthe piston walls, may be a se arate plate 76 bolted or otherwiseattached to the piston. At 77 is indicated a hole in this plate topermit the plate to pass down over the air outlet pipe 7 8 on thedownward movement of the piston. The air outlet pipe 78 is like theoutlet air pipe 21 of the preceding figures,

air flow. Valves corresponding to the valves- 33 may be used, however,if necessary, as ine dicated at 80, although the superior suctionproduced by or with the aid of the blower tends to render even thesevalves unnecessary. The presentfigures also illustrate that the incomingair can be taken 1n at 81, that is to say at the top of the caseenclosing the valve rockers and after passing through thisvalverocker-case 82, passed down through the pipe 83, around the pushrods 84, and thence to the intake pipe 79; thus the entirevalveoperating system is cooled. They also illustrate that the outletmanifold 85 may be simply a pipe laid lengthwise of the engine andslotted at intervals opposite the feet of the outlet pipes 78; at theseoutlets are located brackets 86, each of which contains a flap valve forthe corresponding outlet pipe 7 8 while yokes 87 and bolts 88 draw thepipe down against the brackets 86 with the slots opposite passagescontaining the valves 80. The blower 75 is interposed between the outletof the manifold 85 and the intake of the carburetor, which are connectedto the inlet port and outlet portof the blower respectively. An oil trap89, however, with an oil return pipe 90, may be inserted between themanifold and the blower. In Fig. 10 the blower is shown as separatelydriven, that is to say, driven by an electric motor 91, and the motor 91may be a source of regulation by affording regulation of the speed ofthe blower. As an alternative the blower may be driven by the engineitself, as directly by the fan belt 100 as shown in Fig. 12. In eithercase I ordinarily insert a regulating valve between the blower and thecarburetor choke 40. The regulating valve illustrated com prising achamber or part of the passage may open at one side and a valve 96 withtwo wings pivoted midway in the opening so that it can simultaneouslyopen the blower outlet and the carburetor intake to the atmosphere aswill be apparent from Fig. 10. In the pres ent instance I haveillustrated the regulation for this regulating valve 96 as entirelyindependent and in no way connected to the throttle 7 or choke 40; it isnot essential. however, that this valve be unrelated to the enginecontrols.

As before explained, a blower provides an adequate flow of air both forcontamination prevention and piston cooling under all condition withoutrestricting the power output of-the engine. Indeed the engine may besupercharged by the blower, that is to say,

the combustion or fuel mixture delivered tothe combustion spaces atsuper-atmospheric pressure, so that by one system I can prevent crankcase contamination, moderate the temperature of the pistons, andincrease the power of=the engine by supercharging.

Figs. 13 and 14 illustrate modifications of the contamination-preventionfeature of my invention in which the escaping fuel is returned to thecombustion spaces directly. These figures show sections of enginepistons. Referring first to Fig. 1-3 Adjacent: the top of the piston isplaced a pierced liquidcollecting ring 106 similar to an oil ring, whichcan be'denominateda fuel collecting ringrather than an oil collectingring because of its position and principal function. The centralportionof the piston top or head is depressed to form a receivingchamber for the fuel at a pointon thepiston when the temperatureishigher than directly at the crevice and liquid fuel entering the crevicebetween the piston and its cylinder wall is goicollected by the ring 106and-directed by the inclined passages-107, into the receiving chamberwhence itmay be vaporized by the piston and consumed by the heat ofcombustion.

Obviously vaporizing from the recaptured liquid fuel is delivereddirectly into the combustion space. The-inclining of the passage 107prevents fuel liquidbeingfed backwards toward the cylinder walls, andthe'passages may open into the depression above the lowest point thereoffor the same result. If desired this arrangement maybe used incombination with and supplemented by an internal lip such as 17 with itspassages 10and collecting ring 12 before described. If carbon tends tocloseisuchpassages as 107 unduly, they may be made in more generousproportions, other forms adopted or arrangements made to avoid theaction. Thus, for example,in Fig.,

14, the outlet of each passage 107 lies in a plane making a sharp anglewith the general plane of the piston head. Furthermore a flange-likeprotuberance 108 extends. inwardly over the piston head proper partiallyclosing the receiving chamber on the head of the piston whereby it tendsto retain unconsumed' liquid fuel on the heated surfaces for a longertime for vaporization purposes. The throat of the chamber may be made ofproportionate size to give the best results, the flange being enlargedif necessary or desirable as indicated by the broken lines 109. I

believe it is better to open the outlet ends, of.

' the passages 1071above the edge of the lip flange 108,.as illustrated,rather than below it, in order that any-liquid that may be thrown oilthe floor of the receiving chamber may not be thrown directly into thepassages. The

pistons of these Figs. 13 and 14 and of Figs.

15 and '16 also may be assumed to be used with any ordinary carburetortype of engine using liquid fuel of considerably lighter gravity thanthe engine lubricant.

In Fig. 15 the fuel vapor is also delivered substantially directly intothe combustion chamber for immediate use, the receiver or receivingchamber 115 for the liquid fuel being'entirely closed however so thatthe liq-.

uidis shielded from direct contact with the flame in the combustionchamber. The chamber 115 it will'be observed is within the piston, asillustrated, between two piston heads retaining plug is set in at 120.In vertical v engines at least I do not contemplate that a spring or anyother arrangement will :be'need ed to hold the valve to itsseat, for onthe working stroke the pressure Withinthe combustion space holds thevalve down, and on the compression and exhaust strokes (fourcycleoperation is assumed) the piston moves against the valve and'is somewhatsupplemented by pressure. On the suction stroke I desire the Valve toopen, and both the inertia of the valve and the suction in the com vbustion chamber tend to open it. Suction is then applied to the chamber115 to evacuate it: and I contemplatethat suction will be applied inthis manner to the passages 117' throughout the major part of eachsuction stroke, so that at least every fourth stroke.

applies suction to the cylinder wall to sweep off escaping fuel. In sofar as the chamber 115 continues at reduced pressure after the valve 119closes, suction is applied to the cyl-,

inder wall during the other strokes also. The outlet passages 118 may beelongated as illustrated, that is, its entrance located rather close tothe flooror a sump of the chamber if it is desirable to returnrecaptured fuel to the combustion chamber in liquid form at.

any time, for example in case the chamber 115 should receive some timean overcharge of liquid fuel. The recaptured fuel is returned to thecombustion chamber in the form of vapor however, proportionally to theeleva- V tion of the entrance of'118 above the chamber bottom.

The modification of Fig. 16 is rather similar to that of Fig. 15 inprinciple but is a form in which the invention can be applied tostandard pistons. .The piston head is opened at the center and threaded.Into this opening is screwed the plug having a receiver or receivingchamber 126 for therecaptured fuel,

valve 127, and pierced valve retaining' plug 128. As before, theescaping fuel maybe recaptured in the circumferentialgroove129 (in whichmay be seated a fluid-collecting ring asbefore). Pipes 130 (as many asmay conduct into the hollow of returns directly to the combustion space.By opening a passageway 131 from the hollow of the piston to the chamber126, suction strokes will tend to withdraw vapors from the cylinderspaces and crank case also, and return them directly to the combustionspace. The construction can be supplemented by a lip 17 ports 10 andcollecting ring 12 such as shown in Fig. 1, for example, if desired, thevapors produced within the piston hollow by these means being returnedto the combustion space directly instead of in the more roundaboutmanner illustrated in Figs. 1 to 7 in the alternative the lip, etc. withthe passage 130 and valve 127, or analogous constructions,

may be used without the passages 131. If desired, either passage 130 orthe up-rising passage leading directly to the valve 127 may be providedwith valves for manual adjustment.

It will be understood that my invention is not limited to the details ofconstruction illustrated and described above, except as appears in thefollowing claims.

I claim:

1. In an internal combustion engine, means to retain on a piston untilvaporized the liquid fuel passing the piston head, and a receiver forthe products of such vaporization to keep the same from reaching themain stock of engine lubricant.

2. In an internal combustion engine, a piston having a recess to receiveliquid fuel reaching the piston, and means for removing, from the enginecase, products of vaporization from the liquid reaching said recess.

3. In an internal combustion engine, a hollow piston having an internalliquid-receiving recess opening to the hollow in said piston, a port topass liquid fuel into said recess, and means for receiving products ofvaporization from the liquid reaching said recess to keep fuel fromdiluting the stock of engine lubricant.

4. In an internal combustion engine, a hollow piston having a port topass into the hollow of the piston fuel reaching the piston in liquidform, and means for removing fuel reaching the hollow of the pistonwithout mixing said fuel with the main stock of lubricant in the engine.

5. In an internal combustion engine, a hollow piston having a port inits side wall to the piston liquid fuel passing the piston head, andmeans for removing such fuel from the engine case, said means taking thefuel from the piston.

6. In an internal combustion engine, a hollow piston having a port topass into the hollow of the piston fuel reaching the piston in liquidform, said piston being adapted to retain liquid fuel passed into itshollow until said fuel is substantially entirely vaporized, and meansfor removing the fuel vapor from the engine case substantially asrapidly as it 1s formed.

7. In an lnternal combustion engine, a hollow piston having a port inits side wall to conduct into the hollow of the piston liquid fuelpassing the piston head, said piston being adapted to vaporize fuelwithin it, and means for removing such fuel vapor from the engine case,said means taking the fuel vapor from within the hollow of said piston.

8. In an internal combustion engine, a hollow piston having a port inits side wall to conduct into the hollow of the piston liquid fuelpassing the piston head, and having a baffle extending inwardly from thepiston side wall below said port to restrain the flow of liquid enteringthe piston through said port.

9. In an internal combustion engine, a hollow piston having a port inits side wall to conduct into the hollow of the piston liq- ,uid fuelpassing the piston head, and having a baffle extending inwardly from thepiston side wall below said portto restrain the flow of liquid enteringthe piston through said port, and means for removing from the enginecase the fuel vapor produced by the piston.

10. In an internal combustion engine, a hollow piston adapted tovaporize liquid fuel tending to pass the piston and deliver the vaporinto the hollow of the piston, passageway means providing an outlet forthe vapor leading from the hollow of the piston, and means for applyingsuction to said passageway.

11. In an internal combustion engine, a hollow piston adapted tovaporize liquid fuel tending to pass the piston and deliver the vaporinto the hollow of the piston, passageway means providing an outlet forthe vapor leading from the hollow of the piston,

passageway means providing an inlet for air opening into the hollow ofthe piston, and means for applying suction to said outlet passageway.

carburetor for the engine, said passageway leading to a carburetor airintake so that a vapor-removing air flowis created.

13. In an internal combustion engine, a hollow piston adapted tovaporize liquid fuel tending to pass the piston and deliverthe vaporinto the hollow of the piston, two

stand pipes extending into the piston when the piston is at the end ofits working stroke, and a carburetor for the engine, one of said standpipes leading to an air intake of the carburetor and theother'stand'.pipe providing an inlet for air.

14. In an internal combustion engine, a hollow engine piston adapted toliquid fueltending to deliver. the fuel vapor into the hollow of:

the piston, and an outlet pipe. arranged to' conduct such vapor away,saidoutlet pipeder chamber to a .point close to the piston head when thepistonv isat the endof a .power stroke.

16. In an internal combustion engine, a: hollow engine piston adapted tovaporizeliquid fuel tending to pass thepiston and deliver thefuelvaporinto. the hollow ofthe piston, and'a pipe to-admitair to theengine case to sweep out such fuelvapo'r, saidpipei reaching into theinterior of the; piston and delivering air therein. 7 17. In an internalcombustion engine; a

deliver the fuel vapor into the hollow-ofthe piston,- and a pipe toadmit air to the engine case tosweep-out' such fuel vapor, said pipe"being a stationary stand pipe reaching into the cylinder chamber to apoint close to the piston head when the pistoniisat theend=of a powerstroke.

18. In a multi-cylinder internalcombustion engine a plurality of hollowpistons,

I l ports in the sides thereof to pass into the hollows. of thepistonsthe liquid fuel tending t to pass the pistons, means withinthepistons to retain said liquid fuel on the. pistons until vaporizedthereby, a stationary air-inlet stand pipe and a stationary outlet standpipe extending into each of said pistons to ad acent the head thereofwhen the respective piston V is at the end of its working stroke, a:blower, :the intake of which is connected-to saidoutlet pipes, aflow-operated valve in each of said outlet pipes to prevent flowtherethrough 1nto the respective cylinder chamber, a carburetor, anair-intake of which is connected to the Q discharge of said blower, saidblower be ng retor into the combustion spacesofthe engine atsuperatmospheric pressure, and-011 trap meansinterposed in'thelinebetween the vaporizepass the piston and hollow engine piston adaptedto. vaporize liquid fuel tending to pass the piston and adapted todeliver air through said carbu by thefactthat the. said valveisiconnected to one of the engine controls andisadjusted thereby.

V 21. In an internal. combustion engine, means for permitting a flow ofair througha cylinder chamber of the engine, between the head of thepiston therein andthe crank shaft, a blower tending to produce suchflow, a car'- buretor' for the engine, passageway means;

directing such flow into an. air intake of the carburetor, and a valvefor opening saidpassageway means tothe atmosphereto a regulatableamount. r

22. An internal combustion engine having a carburetor, characterized bythe fact that a piston thereof hasia receiving chamber forliquid fuelwithin its cylindrical Wallstore ceive and vaporize fuel, and that thecylindrical wall of the piston is pierced with a passageway to conductliquidfuel into said re- COIVGL- I p 23. The engine of claimr'22,further characterized by the fact that a liquid collectingring on thepiston directs liquid fuel into the pierced passageway.

24-. An internal combustion enginehaving means at the side of the pistonto collect liquid .fuel tending. to pass the piston and deliver it forvaporization to a. portion ofthe piston hotter than the side of thepiston.-

25. An internal combustion engine having a carburetor for its fuel,characterized by the fact that the side of 'the piston-is provided withapassage to direct liquid fuel tending to pass the'piston, to a portionof thepiston nearer its axis-where the fuel issubject to greater heat tovaporize it.

26. In an internal combustion engine, the combination of a hollow enginepiston having a passage for passing into the spacewithin the guidingskirt of the piston fuel;tend-' ing to pass the piston, and meansforsucking fuel from within the skirt and returning it to a combustionspace of the engine;

27-1w an internal combustion engine the combination of a hollow enginepiston having a passage for'passing into the piston fuelv tending topass the piston, the piston-being porized, and means for withdrawingthefuel vapor from withinthe it; to the engine.

In testimony whereof, I have signed this specification.

. RUSSELL S. CARTER adapted to retain the liquid fueluntilivapiston andreturningv

